This invention relates to an optical cable and an optical cable line composed of the cable.
In a commercial communication line, maintenance and replacement works to be carried out in the alteration of a facility, a start of a branch station, an increase in a unit and an alternation of a route upon execution of a municipal maintenance plan are always conducted frequently, and the switching works of cables are also performed at every time of the works. Since it is necessary to instantaneously execute the switching of channels of cables without momentary disconnection, double channels are provided in the line at the switching time to remedy against the execution of the switching works. In case of a metal communication cable, a branch connection can be readily carried out while the channels are alive if the core conductors are exposed by removing the coating of the core wire of the insulated wire, and the double channel can be readily performed in the line.
However, in case of an optical cable, since a continuity cannot be obtained even by contacting the side faces of a bare fibers by removing the coatings of the core wires of the optical fibers, it is not simple like a metal cable to prepare the line in double channels while the channels are alive. This is a large disadvantage of the optical cable line.